1. Field of the Invention
The present invention relates to a resist pattern-insolubilizing resin composition and a resist pattern-forming method using the same.
2. Discussion of the Background
In the field of microfabrication (e.g., production of integrated circuit devices), lithographic technology that enables microfabrication with a line width of 0.10 μm or less has been desired to achieve a higher degree of integration. As a resist that is suitable for excimer laser light, various resists (chemically-amplified resists) that utilize a chemical amplification effect due to an acid-dissociable functional group-containing component and a component that generates an acid upon irradiation (exposure) (hereinafter referred to as “acid generator”) have been proposed (see Japanese Patent Application Publication (KOKAI) No. 1993-232704, for example).
Lithographic technology that can form a finer pattern (e.g., a fine resist pattern with a line width of about 45 nm) is expected to be required. Such a fine pattern may be formed by reducing the wavelength of the light source of the exposure system (e.g., ArF excimer laser (wavelength: 193 nm)), or increasing the numerical aperture (NA) of the lens, for example. However, an expensive exposure system is required to reduce the wavelength of the light source. When increasing the numerical aperture (NA) of the lens, since the resolution and the depth of focus have a trade-off relationship, a decrease in depth of focus occurs when increasing the resolution.
In recent years, liquid immersion lithography has been proposed as lithographic technology that can solve the above problems (see Japanese Patent Application Publication (KOKAI) No. 1998-303114, for example).
However, it is considered that liquid immersion lithography can only be applied up to 45 nmhp. Therefore, technical development toward a 32 nmhp generation has been conducted. In recent years, technology that forms a 32 nm line-and-space (LS) pattern by forming isolated line patterns or trench patterns by a half pitch utilizing double patterning (DP) or double exposure (DE) has been proposed to deal with a demand for an increase in complexity and density of devices (see SPIE 2006, Vol. 6153 61531K, for example).
SPIE 2006, Vol. 6153 61531K discloses forming 32 nm lines at a pitch of 1:3, followed by etching. 32 nm lines are formed at a pitch of 1:3 at positions displaced from the first-layer resist pattern by a half pitch, followed by etching to obtain 32 nm lines at a 1:1 pitch.
However, a material that may suitably be used for double exposure utilizing liquid immersion lithography has not been proposed. Moreover, when forming a second-layer resist pattern using the above method after forming a first-layer resist pattern, the first-layer resist pattern may be deformed, so that the lines may be formed with insufficient accuracy.